We have focused our attention on a gene that we found to be up-regulated in a human Parkinson brain. This gene is flotillin-1. Using in situ hybridization histochemistry we observed the presence of flotillin mRNA in the substantia nigra of the human brain, in addition to the n.III N, n.IV N, n.V N, locus coeruleus, pontine nucleus and cerebral cortex. Immunohistochemical and in situ hybridization studies in the rat brain are currently underway. So far, flotillin mRNA and protein have been observed in the substantia nigra/ventral tegmental nucleus, n. basalis, locus coeruleus, arcuate nucleus, supraoptic nucleus,hippocampus/dentate gyrus, paraventricular nucleus of the thalamus and n.V N. This novel gene is of interest because of its presence in vesicles, in addition to its possible involvement in Parkinson's disease.